Hand brake mechanism



Nov. 18, 1952 E. c. MERSEREAU HAND BRAKE MECHANISM 2 SHEETS-SHEET 2 Filed Nov. 15 1950 INVENTOR. EVERA ED CIT P BY ERSEREAU. 4? w Patented Nov. 18, 1952 UNITED: STAT ElSl E OFFICE! HAND BRAKE MECHANISM' Everard- G1.- Mersereau; Westfi'eld', J1, assignon to National BrakmCompa'ny; Inci,v Nevw'Yotl's. N. Y., a. corporation of New York- Applicatibn November 15, 1950, Serial'No. 19517.76

13' i Claims This inventioi'r relates to brake mechanisms: and particularly; to-hand brake mechanismsfor" railway carsinwhich a friction-clutch is employed intermediate a manually operated shaft and a; detentwheel fbrhold-ing a' brakerigging talEe-up'di'um:

Hand brake mechanisms; employing'a friction clutch to interconnect a detent wheel with a manually 'operated shaft which; in cooperation with *agear train, rotates a brakerig-gi-ng take-updrum are wellknownand may, for example, take the forrn shown in UnitedStatesPatentNo: 2,310,135,

or-ac collar; with. a face; perpendicular to. the axis of the shaft: anda threaded portion actingi-as pain of clutch discs are mounted lonthe shaft,- one between. the detent wheel-and :the'pinion and one betweenthe detent wheeland sa-id face v When the above-mentioned shaft is rotated in one direction, thepinionnmoveslaxially ofQthe'. shaft; because of. itslengagement. with a drum drivengear andbeceiuse of. the threads, I'nthis. mannenz tne pinion clamps the detent wheelbe+ tween theiclntch discs causing it to rotate with thesh-a-f-t; When the slraftisrotated in the pposite' direction, the pinion moves away from the detent' wheel, unclampingthe wheel and permitting the shaft and pinion to rotateiwi-th respect to -the wheel-. However;- the: movement of the pinion away"from thedetent wheel is stopped only" '40 member with the face of a shoulder or collar on" by engagement of the pinion or an associated the-shart-orwith-the face of a-housing orbearing supporting the shaft, the face; ineach-in'sta-nce;

being: substantiallyperpendicular to the axis of the pinion; Thus, whenitis' necessary toapply torque: to the-shaft; sufficient" to forcibly release thea-jbrake-rigging'or when the tor-'qne isapplied to: the shaft; in the 1 release direction: after the rigging is fully rel'eased, thepinion is= forcec1'='- against. the associated: stop and may become jammed; thereagainst. such jamming is undesinabie; because when the shaft is again rotated in; the take-up; direction; the pinion will not readiltrxmovetowardi the detentvwheel and cause its-to: rotatewiththe: shaft-particularly if the Generally, in such-mechanisms, themamtally operated shaft has an enlarged portion A detent pinion is j'ammedagainst thestop fora time suffl'cientfor rust to form. This difficulty may be so serious, in fact, that'the brakes of a; car

may be applied without rotation of the detent wheel and hence; without its aid; and in this event, it will not be possible to holdthe brake inan applied position.

It is-an objectof my invention to overcome the above-mentioneddiffi culty and thereby; to provide a clutchoperated hand brake mechanism which isfreefrorlrrjamming;

Accordingly; it" is an object of'my invention to provide an improved hand brake mechanism which is reliabl'ein operation.-

Other objects and advantages of my invention will beapparent -from the detailed description of the invention given' hereinafter-byway of? ex ample only and setting forth the mannerinwhich I now preferto practice the invention.

In 'a'ccordance'with my; invention, the operat ing shaft of the brake mechanism, which-causes" axial movement of-the pinion, is provided-with a stop-member which applies forcetothepi'nion substantial-ly -onlyin a tangential direction and prevents further axial-movement. of the pinion after the pinion has moved axially a distance snflicient to unclamp'the detent'wh'eel'.

In the preferred emtodi'i-nentof mv'invention',

a radially extending member is mounted on the shaft, and} this member hasa stopportionspaced radially from the axis of the shaft" and which extends into the helical pathfollowed'by a stop engaging-- portion of the pinion as the pinionmoves-axially away from" the detent'wheel. Pref era-lily; the faces of-the stop' portion and the stop engaging portionof: the pinion lie" in a plane or planes-passing throughithe: axis of' the emitted that substantially no axial force. is'appiied to the Figi-l is' a fragmentary side elevationviewb partl-y msection, of abrake mechanism incorporaati'ngmyinvention:

ie- 2 is an end elevation view of the driving;

mechani'sm of my invention showing the 'com':

ponent' par-ts thereof in the positions assumed;

Fig": 4 is an end elevationview 0f the driving" mechanism of my invention showing the components thereof in the positions assumed when the brakes of the vehicle on which the mechanism is mounted are released;

Fig. 5 is a side elevation view, partly in section and taken along the line 55 indicated in Fig. 4, of the mechanism shown in Fig. 4; and

Figs, 6 and 7 are enlarged fragmentary views, partly in section, of the mechanism shown in Figs. 3 and 5 respectively.

Referring to Fig. 1, the brake operating mechanism comprises a drum I9 rotatable by a gear II which may be rigidly connected to the drum III. The drum I9 and the gear I I may be mounted on a shaft I2 which may be journalled at its ends in bearings I3 and I l mounted on the housing I5. The drum I0 operates the brake rigging of a vehicle on which it is mounted and may be connected therewith by a chain I6 which is fastened to the drum I!) by a pin IT.

The gear II is rotated by a pinion I8 which in turn is rotated by a shaft I9 supported by bearings and 2| mounted on the housing I5. The shaft I9 may have a square tapered portion 22 which carries a manually operable member, such as hand wheel 23, for manually rotating the shaft I9.

The shaft I9 may have an enlarged portion 24 which, as will be explained in detail hereinafter, cooperates with the pinion I I! to rotatably clamp a detent member, such as a detent wheel 25, causing the detent wheel 25 to rotate with the shaft I9 when the hand wheel 23 is rotated in a clockwise direction, as viewed from the right in Fig. 1. r

The detent wheel 25 cooperates with a pawl 26 pivotally supported by arms 21 and 28 which may be integral with the housing I5. The pawl 26 is pressed into engagement with the teeth on the periphery on the detent wheel 25 by a spring 29. 'Thus, when the brakes of a vehicle on which the-brake mechanism may be mounted are operated by the mechanism, the brakes are held in their operated condition by the cooperation of the detent wheel 25, pawl 25 and the clutch mechanism, including the [clutch membe 24 and the pinion I8 until the hand wheel 23 is rotated in a counterclockwise direction.

As shown in the remaining figures of the drawings, the driving mechanism of my invention may comprise the shaft I9 having the enlarged portion 24 which has a face 39 substantially perpendicular to the axis of the shaft I9. The portion 24 is a clutch member and. is preferably formed integrally with the shaft I9, but it may also be a separate collar pressed on the shaft orotherwise fastened thereto so as to be rotatable therewith. The hand wheel 23 shown in Fig. 1 may be held on the tapered portion 22 of the shaft I9 by means of a nut (not shown) in threaded engagement with threads 3| on the end of the shaft I9.

The shaft I9 may also have a threaded portion 32 which, in cooperation with a threaded portion 33 of the pinion I8, moves the pinion I8 axially upon relative rotational -movement of the, pinion I8 and the shaft I9. The threads of the portion 32 act-as a cam having helical surfaceswhich engage the helical surfaces of the threaded portion 33 of the pinion I8.

A plurality of .clutch discs 34, 35, 36 and 37 are mounted on theshaft I 9 between one surface 38 of the detent whee1 25 and the pinion I8 and between another-surface 39 of the detent wheel 95 and the clutch member 24. When the shaft I9 is rotated in a clockwise direction, as viewed from the right in the figures of the drawings, the pinion I8 because of its engagement with the gea I I and because of the threaded portions 32 and 33 moves axially to the right clamping the clutch discs 3431 and the detent wheel 25 between the surface 40 of the pinion I8 and the surface of the clutch member 24. When sufficient pressure is applied to the clutch discs and the detent wheel 25, the friction between the clutch discs and the surfaces 39, 38, 39 and is such that the detent wheel 25 rotates with the shaft I9. As long as the shaft I9 is not turned in the counterclockwise direction, there will be sufficient friction between the detent wheel 25, the clutch discs, the pinion I8 and the clutch member 24 to prevent rotation of the shaft I9 in the counterclockwise direction and hence, to prevent release of the brake rigging controlled by the drum I0. However, when the shaft I9 is rotated in the counterclockwise direction by the hand wheel 23, the pinion I8 because of its engagement with the gear II and because of the threaded portions 32 and 33 moves axially away from the detent wheel 25, thereby reducing the friction between the clutch discs and the surfaces of the detent wheel 25, the pinion I8 and the clutch member 24. When the friction is reduced, the pinion I8 is free to rotate under pressure from the gear I I and the brakes of the associated vehicle will be released to an extent controlled by counterclockwise rotation of the hand wheel 23, as described in the aforementioned patent.

If, when the shaft I9 is turned in the counterclockwise direction, the gear II is not rotated by the pull of the brake rigging, it may be necessary to rotate the shaft I9 an amount sufficient to cause the pinion I8 to drive the gear II in a direction opposite to the direction in which it was turned when the brakes were applied. When the shaft I9 was so rotated in the counterclockwise direction, in previously known brake mechanisms of this type, the surface AI of the pinion I3 was forced against a face of a stop member, such as a surface 44 of a collar 42 mounted on the end of the shaft I9 and fastened thereto as by a pin 43. The pinion It was, therefore, jammed against the stop member. Similarly, if the brakes were fully released and the shaft I9 was turned in the counterclockwise direction, the pinion I9 would also become jammed against the stop member. Such jamming made the pinion I8 difiicult to release and to return to the clutch engaging position in which position the detent wheel 25 is rotated with the shaft I9. The jamming caused increased difiiculty if the jamming continued for a period of time sufficient for rust to form between the surface 4| and the stop member.

In accordance with the preferred embodiment of my invention, the surface 4| of the pinion I8 is prevented from coming into contact with the surface of a stop member, such as the surface 44 of the collar 42 by providing a stop engaging portion 45 on the pinion I8 and by providing a stop member which rotates the pinion I9, when the detent wheel 25 is unclamped, by applying rotating force to the pinion I8 substantially only in a tangential direction. As used in this specification and in the claims appended hereto, a force applied tangentially to the pinion I8 is intended to mean a force applied transversely to the axis of the pinion l8 at a point on the pinion agencies 52 onazimembers associated therewith. spaced:.-from;. the; axis of theupinion.

I Although in: thezpreferred embodiment of? invention; the: surface; 41'. Ofethl pinion; I8"; is? prevented fromzcomingzintozcontactzwith;thmsursface 44 of? the; stop? member 42;;contactbetween these: surfaces; is "permissible-1 and: within: the: scopezof:thminventionzzprovided thati'the pressure: exerted? by one; surface upon; the: other?- is: not; suflici'enti: to" cause: the: pinion Ia to: jam. against. thez' stop member 42-; The: amount: of pressure: hetweerrthesurfaceswhichi.canbeztoleratedwvitireout: jamming: depends. on". .severaL factors: well. known to: those sliilledf. in: the; art;, such; as; for; exampimmaterials employedpthread. pitch}. Silt-*- f'ace finishes-etc:

Thmstop: engaging: portionr4'5; has; .aszshownain: Figs: 2-: and14-,. a. faces46 which lleszwithima;plane passingvthrough' the.- axis: of pinion. l8: butwhicir: may also: bezconsidered as: facing: in: a; directions; transverse to'the'zaxisiofithez pinion :l 81. 'ITiELEStQD? member 42 has an arcuate portion 4lw-hichzalsot has aiface'idalying within'iaplane'passingzthrough the: axis of the. pinion. I8; Itrwill be. notedrthatt 'thezpinionz l 8,. the; stop. member. 42: and; the: shaft.

required to: apply; the brakes. of arrassociated.

vehicle,-. thezsurface-M istseparated from? the sur. face: 44- andthe pinion I 8 presses itst surfacelfl:

againstthe clutch disc 34: In:thisposition;.the:

face 46' of' the stop: engagingxportion 45 is sepasratedin acircumferentialdirectioncfrom the-face:

48 'of ther'arcuate portion". Theseparatiorrofi the-,- faces. 46 and. 48 occursrbecausetheshaft. I9. is: turned in. a" clockwise: direction. to; causer'the? pinion l8 to, clampthe detent wheel 25-...

Referring next to: Figs. 4- and. '7, the;;pini0nr I 8: moves axially; to the: left when the: shaft-.19: is:

turnedrin .a' counterclockwise: directiomto; release: the. brakes;ofan associated.- vehiclez; Thea'sepazration between: the surfaces 4| and- 443 accordeinglytbecomes less and-.the.-faces.4& and. become: engaged with each other.. Thepositions of: faces. 46. and. 48- are. so, related to. the. pitchrof the;- threadedportions 32' and.33 and.thespacing; of; thesurfacesM and 44 that the-faces: 46 andr4-8- become engaged. beforethe: pinion' l8- contacts.

any portion of" the. stop member; 42: other:than:,.

the. face 48. For example; whenthe. detenti wheel: 2-5iiszclamped by: the.-pinion l8; thefacesMi and; 48' may. be. approximately 60 degrees apart and: the surfaces 4| and. 44 maybe separated: by-i slightly more .than one-sixth of; the: thread pitch; A'sthe clutch discs wear with .use;.the-separationsa: become proportionately, greaten. Further. rota? tion of. the. shaft [9 in. ascounterclockwise direce' tion..causes.the stopmember 42 to rotate. the". phiioniwandathus to turn-.thezgear I l'..

Itiwill be. noted that since. thesforcevapplieds.

to. the face. 461 by theiface; 48 is;.substantially in:

a: tangential direction; these faces do; not: jams. together and: hence; when. it; is; again. desired-1 to;-

apply? theiassociatedl, brakes;. the. shaft. la" man? readily be: turned and.v the pinion: i8 will agai'm; clamp the; detentwheel", 25 .between. the clutch: discs:3.4;and;.35;

Having=.;thus1 described myinventionrwith: pan-- ticular reference: tothe; preferred. form: thereof; and having described certain modifications; it; will be ZObViDlISZtOthOSe skilled in the? art to which thezinvention pertains. after understanding? my? invention; thatvariousnchanges:andotheri'mo'diiw fications'may-bemade therein; without departilgw v from. the; spirit: and. scope". of my: invention defined bythe;claimsappendedhereto:

What: claimed; as: new" and" desired. tobe": secured.byLettersPatent of thes-Unitedl States is:':'

1. Abrak'e operating; mechanism comprisingiia; pinion having: azportionfacing in a direction. transverse. to its: axis; a take-Pup: drum! drivinglyi: connected; with:. said pinion, arotatable: shaft? means operable. by saidishaft' for: moving said. pinion axially". in: two. opposite directions and into first and' second predetermined positions; means; rotatablezby said shaft and engageable-withsaidi. portionzof' said pinion in saidfirst position for" rotating said pinion and' means rotatable by saidi shaft and engageable with said pinion insaid"; secondposition for rotatingsaid pinion and said" drum.

2; Inta brake operatingmechanism, an operating shaft, a" pinion connected to said shaft;

means-"operable by said shaft for moving said" pinion axially in" two opposite directions upon: relative rotation: between said shaft and said pinion; a-detent member'adapted' to be clamped to and' 'un'clamped from said pinion by such axial movementand means operabl'eby said' shaftand" engageable with said pinion upon unclamping of said detent-member for applying a force'thereto at a point .spaced from the axis thereof and directed 'substantially only in a direction transverse t'o said axis. 31 In' a. hand brake, a pinion having a portion facing ina direction transverse to its axisa manually rotatable" shaft, means operable by said"- shaft-for moving said pinion axially'into a first predetermined position and" into a second predetermined position; means rotatable by said: shaft and engageable with saidportion of said pinion in said first. position for rotating said-" pinion, and clutch means operable by said pini'ons insaid" second'position.

41111 a hand brake having a rotatable take-- up -d'rum, means-for rotating'sai'd' drum compris mg a pinion drivingly connected with saiddrum- 7 and having a' portion facing in a direction transverse to its axis and at an angle to a radius thereof; a manually rotatable shaft, means op'-- erable by said shaft for-moving said pinion axial ly'into. afirst' predetermined position and; into" a second predeterminedz'position', means rotatable; by? said. shaft and engageable with said portion: of; said pinion in said: first. position. for rotating saidpinion', a: detent member andv clutch means;

engagebale byisaidpinion inzsaid'second position.

. forxrotating;said-.detent.member:. 5. A hand; brake mechanism comprising. a..ro;- tatable 'ta'ke up' drumandmeans for: rotating said:

drum: comprising: a manually rotatable shaft; a:

pinion drivingly; connected with said; drum. said; --pinionz havingv a. stop engaging portion; a; stop. member rotatableby said shaft, saidstopzmemr. her being engageable. with: said. stop engaging. portion in adirection transverse to theaxis of said: piniorrfor rotating said. pinion; a. detent. wheel=v mounted:.az ii'a'centsaid pinion; a. clutch;

disc mounted between said detent wheel and said pinion; a clutch member mounted adjacent said detent wheel on the side thereof remote from said pinion, said clutch member being rotatable by said shaft; and cam means operable by said shaft for moving said pinion axially in two directions.

6. A hand brake mechanism comprising a rotatable take-up drum and means for rotating said drum comprising: a manually rotatable shaft having a helical cam portion; a pinion drivingly connected with said drum and having a helical cam surface engageable with said helical cam portion for moving said pinion axially in two directions, said pinion having a stop engaging portion spaced radially from the axis of said pinion; a stop member mounted on said shaft and rotatable therewith, said stop member being engageable with said stop engaging portion in a direction transverse to said axis of said pinion with said pinion in a predetermined position; a detent wheel mounted on said shaft adjacent said pinion; a clutch disc mounted on said shaft between said detent wheel and said pinion; and a clutch member mounted on said shaft adjacent said detent wheel on the side thereof remote from said pinion, said clutch member being rotatable by said shaft.

, 7. A hand brake mechanism comprising a rotatable take-up drum and means for rotating.

axial therewith and with the threads of said pinion engaged with the threads of said threaded portion for moving said pinion axially in two directions on said shaft, said pinion having a stop engaging portion spaced radially from the axis of said pinion; a stop member mounted on said shaft and rotatable therewith, said stop member being engageable with said stop engaging portion in a direction transverse to the axis of said pinion; a detent wheel mounted on said shaft adjacent said pinion; a clutch disc mounted on said shaft between said detent wheel and said pinion; and a clutch member mounted on said shaft adjacent said detent Wheel on the side thereof remote from said pinion, said clutch member being rotatable by said shaft.

8. A hand brake mechanism comprising a rotatable take-up drum and means for rotating said drum comprising: shaft having a threaded portion; a threaded pinion drivingly connected with said drum and rotatably mounted on said threaded portion axial therewith and with the threads of said pinion engaged with the threads of said threaded portion, said pinion having a stop engaging portion spaced radially from the axis of said pinion; a stop member mounted on said shaft and rotatable therewith, said stop member being tangentially engageable with said stop engaging portion; a detent wheel mounted on said shaft adjacent said pinion; a pair of clutch discs, one mounted on said shaft between said detent wheel and said pinion and the other mounted on said shaft on the opposite side of said detent wheel; and a clutch member mounted on said shaft adjacent said other clutch disc on the side thereof remote from said detent wheel, said clutch member being rotatable by said shaft.

9. A hand brake mechanism comprising a rotatable take-up drum and means for rotating said drum comprising: a manually rotatable shaft a manually rotatable having a threaded portion; a threaded pinion drivingly connected with said drum and rotatably mounted on said threaded portion coaxial therewith and with the threads of said pinion engaged with the threads of said threaded portion, said pinion having a tangentially engageable stop engaging portion spaced radially from the axis of said pinion; a stop member mounted on said shaft on one side of said pinion, said stop member being rotatable with said shaft and engageable with said stop engaging portion for rotating said pinion; a detent wheel mounted on said shaft on the opposite side of said pinion and having a pair of opposite clutch faces; a pair of clutch discs, one mounted on said shaft between said detent wheel and said pinion and the other mounted on said shaft on the opposite side of said detent wheel; and a clutch member mounted on said shaft adjacent said other clutch disc on the side thereof remote from said detent wheel, said clutch member being rotatable by said shaft.

10. A hand brake mechanism comprising a rotatable take-up drum and means for rotating said drum comprising: a manually rotatable shaft having a clutch member thereon with a face perpendicular to the axis of said shaft and having a threaded portion adjacent said face; an internally threaded pinion drivingly connected with said drum and rotatably mounted on said threaded portion coaxial therewith and with the threads of said pinion engaged with the threads of said threaded portion, said pinion having a stop engaging portion spaced radially from the axis of said pinion and said stop engaging portion having a face lying in a plane parallel to and passing substantially through the axis of said pinion; a stop member mounted on said shaft on the side of said pinion remote from said clutch member, said stop member being rotatable by said shaft and engageable with the face of said stop engaging portion; a detent wheel mounted on said shaft and having a pair of opposite clutch faces perpendicular to the axis of said shaft; and a pair of clutch discs, one mounted on said shaft between said detent wheel and said pinion and the other mounted on said shaft between said detent wheel and the face of said clutch member.

11. A hand brake mechanism comprising a rotatable take-up drum and means for rotating said drum comprising: a manually rotatable shaft having a clutch member thereon with a face perpendicular to the axis of said shaft and having a threaded portion spaced axially from said clutch member; an internally threaded pinion drivingly connected with said drum and rotatably mounted on said threaded portioncoaxial therewith and with the threads of said pinion engaged with the threads of said threaded portion, said pinion having a stop engaging portion spacedradially from the axis of said pinion and said stop engaging portion having a face lying in a plane parallel to and passing substantially through the axis of said pinion; a stop member comprising a collar mounted on said shaft on the side of said pinion remote from said clutch member, said collar being rotatable by said shaft and having a stop portion engageable with the face of said stop engaging portion with said pinion spaced from the remainder of said collar; a detent wheel mounted on said shaft and having a Pair of opposite clutch faces perpendicular to the axis of said shaft; and a pair of clutch discs, one mounted on said shaft between said detent wheel and said pinion and the other mounted on said shaft between said detent wheel and the face of said clutch member.

12. A hand brake mechanism comprising a rotatable take-up drum and means for rotating said drum comprising: a manually rotatable shaft having an enlarged portion with a face perpendicular to the axis of said shaft and having a threaded portion spaced axially from said enlarged portion; an internally threaded pinion drivingly connected with said drum and rotatably mounted on said threaded portion coaxial therewith and with the threads of said pinion engaged with the threads of said threaded portion, said pinion having a stop engaging portion spaced radially from the axis of said pinion and said stop engaging portion having a face lying in a plane passing through the axis of said pinion; a stop member comprising a collar mounted on said shaft on the side of said pinion remote from said enlarged portion, said collar being fastened to said shaft and having an arcuate portion spaced radially from the axis of said shaft a distance at least equal to the distance of said stop engaging portion from the axis of said pinion, said arcuate portion having a face lying in a plane passing through the axis of said shaft and being engageable with the face of said stop engaging portion with said pinion spaced from the remainder of said collar; a detent wheel mounted on said shaft and having a pair of opposite clutch faces perpendicular to the axis of said shaft; and a pair of clutch discs, one mounted on said shaft between said detent wheel and said pinion and the other mounted on said shaft between said detent wheel and the face of said enlarged portion of said shaft.

13. A hand brake mechanism comprising a rotatable take-up drum and means for rotating said drum comprising: a manually rotatable shaft having an enlarged portion with a face perpendicular to the axis of said shaft and having a threaded portion spaced axially from said enlarged portion; an internally threaded pinion rotatably mounted on said threaded portion coaxial therewith and with the threads of said pinion engaged with the threads of said threaded portion, said pinion having a stop engaging portion spaced radially from the axis of said pinion and said stop engaging portion having a face lying in a plane passing through the axis of said pinion; a stop member comprising a collar mounted on said shaft on the side of said pinion remote from said enlarged portion, said collar being pinned to said shaft and having an arcuate portion spaced radially from the axis of said shaft a distance at least equal to the distance of said stop engaging portion from the axis of said pinion and said arcuate portion having a face lying in a plane passing through the axis of said shaft and being engageable with the face of said stop engaging portion with said pinion spaced from the remainder of said collar; a detent wheel mounted on said shaft and having a pair of opposite clutch faces perpendicular to the axis of said shaft, said wheel also having detent teeth on the periphery thereof; a pair of clutch discs, one mounted on said shaft between said detent wheel and said pinion and the other mounted on said shaft between said detent wheel and the face of said enlarged portion of said shaft; a gear drivingly connected with said drum and engaged with said pinion; and a stationary detent engaged with said detent teeth.

EVERARD C. NIERSEREAU.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 22,427 Van Cleave Jan. 25, 1944 788,606 Scott et a1. May 2, 1905 1,487,686 Huntley Mar. 18, 1924 1,860,549 OConnor May 31, 1932 1,975,961 Lindeman Oct. 9, 1934 2,000,078 Haseltine May 7, 1935 2,267,037 Mersereau Dec. 23, 1941 2,280,180 Van Cleave Apr. 21, 1942 2,310,135 Van Cleave Feb. 2, 1943 2,313,602 Van Cleave Mar. 9, 1943 2,349,146 Dickson May 16, 1944 2,416,251 Camp Feb. 18, 1947 

